“…So far, the catalysts combining catalytic properties of P 2 O 5 /SiO 2 (good selectivity [9]) with supported HPAs (high conversion and availability [10]) through mixing of phosphoric acid with ammonium molybdate, followed by impregnation of the obtained solution on the silica gel, and followed by heating, were successfully prepared. As a result, mixed catalysts composed of PO 4 3− ions built in the structure of surface Mo ∞ O 3∞ lattice (heteropolyanion-like species) were obtained.…”